Colorimeter



Aug. 17, 1937.

L.. GROSS 2,090,041

COLORIMETER Filed April 10, 1956 m TIT-T 14 E lNvEN-ro'R L GROSSATTORNEY Patented Aug. 17, 1937 UNITED STATES PATENT -OFFICE f 2,090,041I l corlormvln'rlm` Louis Gross, New York, N. Y. A Application April 1o,193s, serial No. 73.633 3 claims. (Cl. :z8- 14) vessel having in itsbottom an optical chamber bounded by parallel transparent walls holdinga flowing into a compartment adjoining the optical chamber and one ortwo at transparent color standards aligned with the optical chamber forcomparing and matching the color of the liquid contained in the chamberand the compartment with the color of the standards. A smallgraduatedsyringe connected to the bottom of the optical compartment serves toYstir and to malntain the solution uniform and enables accurate,

quick determination of its characteristics ybyA withdrawing the testedliquid into the syringe and reading on the scale the volume of theliquid required `to match the color standards.

The foregoing'and other objects of the inven-A y o tion will be bestunderstood from the following description of exemplications thereof,reference being had to the accompanying drawing, wherein Fig. 1 is avertical sectional view of a color' imeter of the invention;

Fig. 2 is a similar view along line 2-2 of Fi`g. 1; Fig. 3` is ahorizontal sectional view through the optical compartment along line 3-3of Fig. l; Fig. 4 is a view similar to Fig. 1 of a modiiled form of theinvention;

Fig. 5 is a horizontal sectional 'view of th modification alongline 5-5of Fig. 4; and

Fig. 6 is a view similar to Fig. 5 of a further modification'.

The calorimeter shown in Figs. 1 to 3 com- 40 prises a small test vesselI0 having a bottom portion of small volume serving as an optical chamberII communicating with an upper wider overflow chamber I2. The opticalcompartment II is bounded by two at transparent glass walls I4- 45conning a at layer of liquid of xedthickness which together with theglass walls I2 constitutes a flat passage transmitting light through thecompartment. On the opposite sides of the optical chamber are mountedilat transparent color standards I6 made, for instance, of suitablycolored glass. 'I'he color standards are held in place against the sidewalls of the opticalk chamber by springs I8 attached to the walls of 55the overiiow compartment to permit quick subat layer of liquid that isto be tested overstitution of one set of color standards for anp-Iother.

, `-Into an outlet opening 20 in the bottom of the,

test vessel is inserted the inlet nozzle 2I of a small glass syringe 22having a piston 23 for withdrawing liquid from the vessel `Iii into thesyringe barrel and measuring the withdrawn liquid on a scale 25 providedon the syringe.

This combination of a simple attachment with a standard syringeconstitutes a lreliable colorimeter and enables vready and exactdetermination of the characteristics of the tested liquid. The lcolorstandards on both sides Vof the op,- tical chamber maybe'made ofthecolorof a standardsolution` containing a 'predetermined quantity.- ofa speciilc ingredient in a. predetermined quantity of a specic liquidsolvent. A.

predetermined quantity of this standard solution lling `a part of theoverflow compartment and the entire optical compartment vwill, if withfdrawn into the syringe barrel, give areading on the syringe scalecorresponding to the standard solution which may be designated as a 100%solution.

'To determine the percentageof the same ingredient of an unknownspecimen to be tested, the same predetermined quantity of the un# knownspecimen is placed in the optical compartment and sufficient solvent isgradually added until the color of the solution lling the opticalcompartment matches the color standards 'of the attachment.`- Asadditional solvent is added to the solution, the syringe piston ismoved'down and up to stir up the lsolution and renderit uniform enablingquick andv accurate matching of the color ofv the solution with thestandards. `Once the color of 'the' solution is matched with thestandards, it is withdrawn into the barrel of the syringe and thereading on the syringe scale en ables ready determination of the amountof the ingredient present in the unknown specimen. 'I'he scale on thesyringe may be designed to give direct readings of the percentage of theingredient, or a syringe with a standard volume scale may be used inconjunction with a calibration chart for determining the percentage ofthe ingredient.

In Figs. 4 and 5 is shown a modiiication of the invention in which thetest vessel is made in the form of a flat block 30 having a largeoverflow l thickness lling the chamber.

Standard color .tion using a testvessel similar to that shown in Figs.4y `and V5 provided ,with colorl standards it consisting of transparentflat glass'vessels tllied with a ilat layer of a standard solution,permitting ready adaptation oi' the calorimeter i'or any a desiredmeasurements.

The exempliiications of the invention described i above will suggest `tothose skilled in the -many other ways of combiningvwithinfa `containeroi.' a dilution type calorimeter a vflat optical compartment and agraduated cylindrical compartment arranged to permit ready mixing of thetested liquid with additional solvent and thek determination by thegraduations of the cylin-y drical compartment oi' the total volumey ofthe.

diluted liquid within the container at :which the;

layer of the liquid in the flat optical compartmentv matches a standardspecimen. z It is accordingly desired that the appended claims be givena construction commensurate with the scope of the.

invention. Y l,

I claim:

l.` In a dilution type: colorimeter'afor determin-n ing the colorintensity ot a liquid by varying its color concentration -until *itsicolorA intensity matches the color oi--a `standard,-a graduated syringevessel for measuring thevolume of the tested liquid, an optical chamberof sx'nallvol-v ume connectedtoone endo! said syringe vessel an openovernow compartment shaped and` proa pox-tienes t0 hold apart or' the.tested .liquid and receive additional liquid for.' diluting the totalvolume of the tested liquid, said optical 'chamber` being. bounded bytransparent walls confining. a

iraction'of the volume of theftested liquid inthe form of a ilatlayer-oi' predetermined thickness for` transmitting light in aydirection perpendicular to lsaid layer, a standard--.transparent colorspecimen aligned adjacent to said optical chamber for transmitting lightin a direction substantially parallel to the direction of the lighttrans-l mittedthrough said chamber,4 and aplston yntting into saidsyringe vessel and `movable therein-.to mix quantities of liquid addedto saldi overilow compartment with tested liquid contained in saidchamber and said compartment i'or diluting the total volume oi'testedliquid with the added liquid and kproducing an increased, volume oftested liquid of. unii'ormk color `intensity insaidoptical chamber andsaid overflow compartment.`

2. In a dilution-type colorimeter for determining the colorintensity'oi! aliquid by varyingits color concentration vuntil its colorintensity matchesthe color of a standard, a graduated syringe vessel formeasuring the volume of the tested liquid, an optical chamber of smallvolume located at one-end oi said syringe vessel, an open overflowcompartment shaped and proportioned to hold a part of the tested liquidandv receive additional liquid for diluting-the total volume of thetested liquid, said optical chamber vbeing bounded by ilat paralleltransparent walls con-A ynning a fraction .of the volume ofthe testedliquid in the form of a tlatlayer of predetermined fixed thicknessfortransmitt'ing light in a direction perpendicular to said Vllat layer,a hat standard 'transparent color specimen aligned adjacent to saidoptical chamber for transmitting light in a direction ysubstantiallyparallel to the direction of' the light transmitted through saidchamber, and a piston tting .into said syringe vessel and movabletherein to mix quantities of liquid added to said overilow compartmentwithv tested liquid contained in said chamber and said compartmentforrdiluting the total volume with the addedliquid y.

and producing an increased volumseortested liquid ofuniform,r colorvintensity rin/ said optical chamber and said overilow compartment, the.

transparentl areas oi' said optical chamber and f said ,color specimenbeing sufilcientlyfsmall andj y lying in sumcient proximity to eachother to bring` the light rays passing through chamber and said specimenwithin the normal range of vision o! lthe observer.

ing the color intensity of.` a liquid by varying its -colorconcentration until its vcolor intensityk matchesthe color ofy astandard, containermeans for holding a volume` of tested liquid.havingran opening i'orreceiving additional liquid and'dilut- -ingthetotal volume oi the tested liquid,a por tion of said container meansconstituting-.an optical chamber bounded by transparent walls conning afraction of the volume of*- the tested liquidA in the form of atlatlaverv of predetermined thickness for transmitting lightin adirection perpendicularto said layer, a standard transparent colorspecimen aligned adjacent-to saidopticai chamber for transmitting lightin a direction substan-H tiuyipsrtnel t0 the direction 0f the lighttransmitted through said chamber, and means for agitatingthe liquidwithin said containing means and mixinsliquid added to the tested liquidwith tested liquid to produce an increased volume oi tested liquid ofuniformj color intensity in said container means. v a portion of 'said`kcontainer means constituting a graduated cylindrical measuringcompartment constructed kand arrangedto measure and indicate the total-volumev ofthe diluted tested liquid ccmtmnedl in said container lALourscao'ss.` f "w

